Shell script to convert video to mp3

The following shell script takes a video file as input and converts it into mp3 file at users home directory.Ensure that the file name is specified in double quotes if it contains any whitspaces.

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#!/bin/sh


folder="/home/$USER/Music"
name=""
if [ -z "$1" ]
then
    echo "No file name specified "
    echo "Please provide the absolute path of the file Ensure that the file name is enclosed in single quotes"
    exit 1
fi

echo "Output file name?"
read name
ffmpeg -i "$1" -acodec libmp3lame -ab 160k -ar 44100 -ac 2 "$folder/$name" 
if (($? != 0 ))
then
    pacman -Q lame ffmpeg > /dev/null
    if (($? !=0))
    then
        echo "Please ensure that lame and ffmpeg are installed on your system"
        exit 2
    else
        echo "No such file exists"
        exit 3
    fi
fi
echo "File successfully converted"
exit 0

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